Hydrangea plant named ‘Ilvobo’

ABSTRACT

A new and distinct cultivar of  Hydrangea  plant named ‘Ilvobo’, characterized by its compact, upright and mounded plant habit; freely branching habit; early and freely flowering habit; strong and sturdy stems that hold inflorescences upright; and large conical inflorescences with numerous white-colored sterile flowers that with development become red purple in color.

Botanical designation: Hydrangea paniculata.

Cultivar denomination: ‘ILVOBO’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Hydrangea plant, botanically known as Hydrangea paniculata and hereinafter referred to by the name ‘Ilvobo’.

The new Hydrangea plant is a product of a planned breeding program conducted by the Inventor in Melle, Belgium. The objective of the breeding program was to develop new compact and early flowering Hydrangea plants with strong stems and attractive flower coloration.

The new Hydrangea plant originated from an open-pollination during the summer of 2003 of the Hydrangea paniculata ‘Pink Diamond’, not patented, as the female, or seed parent and an unknown selection of Hydrangea paniculata as the male, or pollen, parent. The new Hydrangea plant was discovered and selected by the Inventor during the summer of 2005 as a single flowering plant from within the progeny of the stated open-pollination in a controlled environment in Melle, Belgium.

Asexual reproduction of the new cultivar by softwood cuttings in a controlled environment in Melle, Belgium since July, 2005 has shown that the unique features of this new Hydrangea plant are stable and reproduced true to type in successive generations of asexual reproduction.

SUMMARY OF THE INVENTION

Plants of the new Hydrangea have not been observed under all possible environmental conditions. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘Ilvobo’. These characteristics in combination distinguish ‘Ilvobo’ as a new and distinct Hydrangea plant:

-   -   1. Compact, upright and mounded plant habit.     -   2. Freely branching habit.     -   3. Early and freely flowering habit.     -   4. Strong and sturdy stems that hold inflorescences upright.     -   5. Large conical inflorescences with numerous white-colored         sterile flowers that with development become red purple in         color.

Plants of the new Hydrangea differ from plants of the female parent, ‘Pink Diamond’, in the following characteristics:

-   -   1. Plants of the new Hydrangea are more compact than plants of         ‘Pink Diamond’.     -   2. Plants of the new Hydrangea have smaller sterile flowers than         plants of ‘Pink Diamond’.

Plants of the new Hydrangea can be compared to plants of Hydrangea paniculata ‘DVP Pinky’, disclosed in U.S. Plant Pat. No. 16,166. In side-by-side comparisons conducted in Grand Haven, Mich., plants of the new Hydrangea differed from plants of ‘DVP Pinky’ in the following characteristics:

-   -   1. Plants of the new Hydrangea were more compact than plants of         ‘DVP Pinky’.     -   2. Inflorescences of plants of the new Hydrangea did not have         conspicuous fertile flowers whereas inflorescences of plants of         ‘DVP Pinky’ had conspicuous fertile flowers.     -   3. Plants of the new Hydrangea had smaller sterile flowers than         plants of ‘DVP Pinky’.

Plants of the new Hydrangea can also be compared to plants of Hydrangea paniculata ‘Jane’, disclosed in U.S. Plant Pat. No. 22,330. In side-by-side comparisons conducted in Grand Haven, Mich., plants of the new Hydrangea differed from plants of ‘Jane’ in the following characteristics:

-   -   1. Plants of the new Hydrangea were more upright than and not as         rounded as plants of ‘Jane’.     -   2. Plants of the new Hydrangea and ‘Jane’ differ in sterile         flower color as plants of ‘Jane’ have light green-colored         sterile flowers that with development become greyed purple in         color.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the unique appearance of the new Hydrangea plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photographs may differ from the color values cited in the detailed botanical description which accurately describe the colors of the new Hydrangea plant.

The photograph on the first sheet comprises a side perspective view of a typical flowering plant of ‘Ilvobo’ grown in a container.

The photograph on the second sheet is a close-up view of typical inflorescences of ‘Ilvobo’ as the sterile flowers begin to change color.

The photograph on the third sheet is a close-up view of a typical inflorescence after the sterile flowers have become red purple in color.

DETAILED BOTANICAL DESCRIPTION

Plants used for the aforementioned photographs and the following description were grown during the summer and autumn in an outdoor nursery in Grand Haven, Mich. and under conditions which closely approximate commercial Hydrangea production conditions. Plants of the new Hydrangea were three years old when the photographs and description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 2001 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical description: Hydrangea paniculata ‘Ilvobo’. -   Parentage:     -   -   Female, or seed, parent.—Hydrangea paniculata ‘Pink             Diamond’, not patented.         -   Male, or pollen, parent.—Unknown selection of Hydrangea             paniculata, not patented. -   Propagation:     -   -   Type cutting.—By softwood cuttings.         -   Time to initiate roots, summer.—About 20 days at             temperatures of about 20° C.         -   Time to produce a rooted young plant, summer.—About two             months at temperatures of about 20° C.         -   Root description.—Fine and thick; creamy white in color.         -   Rooting habit.—Freely branching; dense. -   Plant description:     -   -   Plant form and growth habit.—Perennial deciduous shrub;             compact, upright and mounded plant habit; broad inverted             triangle; strong and sturdy lateral branches; freely             branching habit with about 35 lateral branches developing             per plant; vigorous growth habit.         -   Plant height.—About 60 cm.         -   Plant diameter or area of spread.—About 50 cm.         -   Lateral branches.—Length: About 40 cm. Diameter: About 6 mm.             Internode length: About 5.5 cm. Texture: Smooth, glabrous.             Strength: Strong, sturdy. Color, developing: Close to 166A.             Color, developed: Close to 197A. -   Foliage description:     -   -   Arrangement.—Opposite, simple.         -   Length.—About 8 cm.         -   Width.—About 3.5 cm.         -   Shape.—Ovate to elliptic.         -   Apex.—Acute.         -   Base.—Obtuse.         -   Margin.—Serrate.         -   Texture, upper and lower surfaces.—Rugose, glabrous.         -   Venation pattern.—Pinnate.         -   Color.—Developing leaves, upper surface: Close to 137A.             Developing leaves, lower surface: Close to 137D. Fully             expanded leaves, upper surface: Close to 137A; venation,             close to 145A. Fully expanded leaves, lower surface: Close             to 137C; venation, close to 145C.         -   Petioles.—Length: About 1 cm. Diameter: About 2 mm. Texture,             upper and lower surfaces: Smooth, glabrous. Color, upper             surface: Close to 166A. Color, lower surface: Close to 145C. -   Flower description:     -   -   Flower type and habit.—Single sterile and fertile flowers             arranged on large terminal conical panicles; flowers face             upright to outwardly.         -   Fragrance.—None detected.         -   Natural flowering season.—Continuous flowering from July             until September in Grand Haven, Mich.         -   Flower longevity, fertile flowers.—Flowers last about four             weeks on the plant; flowers not persistent.         -   Flower longevity, sterile flowers.—Flowers last about four             months on the plant; flowers persistent.         -   Quantity of flowers.—Freely flowering habit with about 1,112             fertile flowers and about 856 sterile flowers per             inflorescence.         -   Inflorescence height.—About 27 cm.         -   Inflorescence diameter.—About 16 cm.         -   Flower diameter, fertile flowers.—About 5 mm.         -   Flower depth (height), fertile flowers.—About 5 mm.         -   Flower diameter, sterile flowers.—About 2 cm.         -   Flower depth (height), sterile flowers.—About 1.5 cm.         -   Flower buds, fertile and sterile flowers.—Length: About             3 mm. Diameter: About 2 mm. Shape: Ovoid. Color: Close to             155C.         -   Petals, fertile flowers only.—Arrangement: Five in a single             whorl. Length: About 2 mm. Width: About 1 mm. Shape:             Narrowly elliptic to ovate. Apex: Acute. Base: Attenuate.             Margin: Entire. Texture, upper and lower surfaces: Smooth,             glabrous. Color: When opening, upper and lower surfaces:             Close to 155C. Fully opened, upper and lower surfaces: Close             to 155C.         -   Sepals, fertile flowers.—Quantity per flower: Five in a             single whorl. Length: About 0.5 mm. Width: About 0.5 mm.             Shape: Ovate. Apex: Acute. Base: Fused. Margin: Entire.             Texture, upper and lower surfaces: Smooth, glabrous. Color,             upper and lower surfaces: Close to 145C.         -   Sepals, sterile flowers.—Quantity per flower: About four in             a single whorl. Length: About 1 cm. Width: About 6 mm.             Shape: Broadly elliptic. Apex: Obtuse. Base: Obtuse. Margin:             Entire. Texture, upper and lower surfaces: Smooth, glabrous.             Color: When opening and fully opened, upper surface: Close             to 155C; color becoming closer to 64A with development. When             opening and fully opened, lower surface: Close to 155C;             color becoming closer to 64A with development.         -   Pedicels, fertile flowers.—Angle: Erect to about 10° from             vertical. Strength: Strong. Length: About 4 mm. Diameter:             About 1 mm. Texture: Smooth, glabrous. Color: Close to 155C.         -   Pedicels, sterile flowers.—Angle: Erect to about 90° from             vertical. Strength: Strong. Length: About 1.5 cm. Diameter:             About 1.5 mm. Texture: Smooth, glabrous. Color: Close to             155C.         -   Reproductive organs, fertile flowers only.—Stamens: Quantity             per flower: About five. Anther shape: Rounded. Anther             length: About 0.5 mm. Anther color: Close to 155C. Pollen             amount: Scarce. Pollen color: Close to 155C. Pistils: Pistil             quantity per flower: Three. Pistil length: About 0.5 mm.             Stigma shape: Elliptic. Stigma color: Close to 155C. Style             length: About 0.3 mm. Style color: Close to 155C. Ovary             color: Close to 155A.         -   Seeds.—Quantity per inflorescence: Numerous. Size: Less than             0.1 mm by less than 0.1 mm. Color: Brown. -   Disease/pest resistance: Plants of the new Hydrangea have not been     observed to be resistant to pathogens or pests common to Hydrangea. -   Temperature tolerance: Plants of the new Hydrangea have been shown     to be tolerant to temperatures ranging from about −30° C. to about     38° C. 

1. A new and distinct Hydrangea plant named ‘Ilvobo’ as illustrated and described. 